FACTICE RQ 20 is a brown sulphur factice that provides swelling resistance for advanced composite materials. As a vegetable oil-based factice cross-linked with sulphur, FACTICE RQ 20 exhibits low swelling behaviour when used in advanced elastomer formulations, comparable to articles based on 18-28% ACN-NBR. Its mineral oil swelling properties make it well-suited for applications involving advanced materials where dimensional stability is required. FACTICE RQ 20 can be used at dosages up to 20% to impart swelling resistance without compromising other material properties important for advanced composite applications. It maintains physical properties at high temperatures suitable for processing advanced materials.